B.C. man believed to be first Canadian to get intravenous gene therapy

A big sushi meal would have once made Josh McQuillin gravely ill, but the British Columbia man can now gorge on one of his favourite foods worry-free thanks to a breakthrough clinical trial for his rare genetic disorder.

McQuillin was 12 when he was diagnosed with urea cycle disorder, a life-threatening condition that causes ammonia to build up in the body and can put a person in a coma.

He had to strictly limit how much protein he ate and took expensive medication several times a day. He could never be too far from a hospital, which made it hard to travel abroad or join friends backcountry camping.

“Now I can eat as much protein as I want. I’m eating differently, sleeping differently, exercising differently,” McQuillin, 30, said during a monitoring appointment at Calgary’s Foothills Medical Centre on Thursday.

“I’ve gained a bit of weight. I’ve never had to fight weight gain before, which is kind of funny. I’ve always been underweight my whole entire life.”

The genes needed to process ammonia were delivered to McQuillin’s liver intravenously. A virus, modified to be harmless, was used as a transmitter. It’s believed McQuillin is the first Canadian to receive gene replacement this way. Only three other people in the world have undergone similar treatment.

McQuillin, who lives in Prince George, B.C., said he felt the results two weeks after the one-time injection.

Aneal Khan with the University of Calgary’s Cumming School of Medicine is leading the trial. He also treated McQuillin in Ontario when he first got sick as a boy.

Khan recalled telling McQuillin’s parents years ago that he wasn’t sure their son would survive.

“Since he’s had this therapy, his ammonia has not gone high, despite him eating whatever amount of protein he wants. It’s a massive change,” said Khan. “We’re very excited — especially for rare genetic diseases, DNA diseases — that we don’t have to tell the parents that stuff anymore.”

Khan said the treatment is being studied for other genetic diseases involving the liver such as hemophilia.

Alberta Health Services has set aside beds in Foothills hospital’s intensive care unit for clinical trial patients. That’s important, because it’s often not known whether an experimental treatment will have serious adverse effects, said Christopher Doig, a medical director in intensive care for the agency’s Calgary zone

“They can get it in a very safe way where they can be very closely watched, very closely monitored. At the same time, we’re not using resources taking away from other patients.”

McQuillin said he’s looking forward to going on a road trip in the United Kingdom this spring without having to worry about his medication or whether the nearest hospital can treat his condition. He can also rest easier when on his forestry job, which once required painstaking meal planning for trips into the bush.

“Everything’s 100 per cent good to go for now,” he said.

“I guess my only concern or fear is they don’t know really how long it will last. But it’s definitely exciting.”